The changes in the spectral densities at the Fermi level with magnetic field should lead to important spatial variations of the differential conductance at small bias.
For \(B=0\)  in the Kondo limit (integer total occupancy),
the spectral densities of the localized orbitals with \(\pi \)  and \(3z^2-r^2\) 
symmetry vanish at the Fermi
surface and the space variation is dominated by conduction states. As \(B\)  increases, the influence of
\(\pi \)  orbitals remains small but that of the cylindrical symmetric \(3z^2-r^2\)  orbitals increase considerably and
therefore, an evolution to a more circular shape is expected, as observed experimentally [1]}.
